Introduction
Liver MRI has been used in cases where ultrasound or computed tomography findings are equivocal. Diffusion-weighted imaging (DWI) established an important role in clinical use in the liver. DWI can potentially add useful information to conventional imaging.
Objective
The aim was to assess the role of DWI in the detection and characterization of hepatic focal lesions and its value to differentiate benign from malignant masses.
Patients and methods
The study included 40 patients, 19 women and 21 men, their ages ranged from 20 to 63 years. All patients underwent detailed MRI study of the abdomen. Diffusion study was performed with tridirectional diffusion gradients using b values 0, 500, and 1000 s/mm to increase the sensitivity. Apparent diffusion coefficient (ADC) maps and values were calculated for all lesions.
Results
In all, 20 patients were diagnosed to have benign lesions and 20 patients were diagnosed to have malignant lesions. Hemangiomas and cysts showed facilitated diffusion while adenomas show restricted diffusion pattern mimicking malignant focal lesions. On the other hand, all malignant lesions showed restricted diffusion evidenced by increased signal on increasing the values and low signal on ADC maps. Mostly benign lesions show higher ADC values than malignant lesions.
Conclusion
Diffusion-weighted MRI sequence with quantitative ADC measurements should be used as an additional sequence to supplement conventional MRI protocol studies for proper characterization of focal hepatic lesions putting into consideration an overlap range.